having read some of your other comments maybe you're making a point about UX -- where the tradeoff between a biometric password or some long and obtuse string o

having read some of your other comments maybe you're making a point about UX -- where the tradeoff between a biometric password or some long and obtuse string of characters (which is thus more likely to be saved in the browser or written on a sticky note) is not as obvious as it seems: which is worse? that's a valid point. and then about usernames: maybe you're just saying, hey i can't just swipe my finger at gmail.com because which gmail account am i logging into? do i need 1 finger for each account (business, personal, etc)? lol that's kind of valid point too but nobody is proposing that the biometric identifier is the only part of the username anymore than your browser fingerprint is (which google does indeed utilize; sign in from somewhere else and you'll get 2FA vs on your own device, etc etc). think of your biometric data more like your phone number in 2fa. its yours and can help to verify your identify but its not secret and your authenticator should be secret